ikay

Could be Status Hotwire flats, they have black silks at both ends.

The damaged windings are probably quite near the surface so one other thing you could try (still fiddly) would be to unwind the top few layers of winding until you reach the last point where it's broken. Then connect this bare end to the corresponding output wire. You'd end up with a few windings less than before but probably not enough to make a significant difference to the tone or output. Might be worth a try before you go for the rewind, not a lot to lose!

You'd need to find and join the corresponding loose ends which would be very difficult to do. Sounds like a rewind to me...

Well looks like it's definitely metric and regular M3 is too small so the next option up is M3.5 as andyjr1515 says. Worth trying as there is a degree of tolerance with the screw diameter so it should fit. If you can find any that is!

Surely open circuit on a single coil would kill the whole pickup not just one string?

I have a Polytune clip as well which is also excellent.

Korg Pitchblack works well for me, big display, easy to use, handles low B no problem.

The Barts will work fine with the Glock. How about just taking out the Glock and rewiring as passive? The snap and bite of single coils are part of what makes a Jazz sound like a Jazz!

That's an unusual one! If the A string pole pieces are no longer magnetic then that would do it, but how that could happen is a bit of a mystery. Sounds like a replacement job to me. Or you could try and re-magnetize the dead poles with a rare earth magnet - https://forums.fender.com/viewtopic.php?f=6&t=100572

This Fender Japan JB-75 on Far East Guitars also has JB-72M in the neck pocket (see pic about halfway down) - http://fareastguitars.jp/fj_jb75-90_3ts_mij_s029/fj_jb75-90_3ts_page.html And this thread on TB mentions the same curiosity - https://www.talkbass.com/threads/fender-jb-mij-75-ri-a-b-serial-1985-86-but-stamped-as-late-90s-jazz-bass.657437/ Sounds like it's normal for a JB-75 and the odd JB-72 pocket stamp is just a mystery!

My old BB1100 used to do this as well. I think it's something to do with how they've wired the active/passive switch so that it also switches the battery in. There's probably a fix using a pull-down resistor (or somesuch technical gizmology) to suppress the pop but I used to just turn down the volume before switching.

If it's in 3/4 something's not quite right after the dotted minim/crotchet rest

See schematic below. These measurements were taken from my original '57 Precision (see pic). Spacing between ferrules is actually 20mm. I'm sure dimensions varied a bit on these early models but this should get you going.

How about an SD Vintage Hot Stack plus? https://www.seymourduncan.com/pickup/vintage-hot-stack-plus-strat?__uuid_ref=5b22959cbd28f This has a bass-heavy voicing (see 'tone profile' halfway down on right) and is hum cancelling to boot. I wouldn't worry about the six open pole pieces not lining up with the strings, the original pickup on my old Musicmaster had six poles and sounded great across all the strings. Out of curiosity why are you only interested in guitar pickups? A bass pickup would give you much more in the way of lows and low mids compared with a pickup voiced for guitar.

If you want a vintage sound then how about a Sentell 'Lil Sis' or 'Big Sis' musicmaster replacement pickup - http://sentellpickups.net/bass.html (scroll down about half way) I have a Big Sis on my Bronco and it's a wonderful thing 😊

Apart from the roadworn cosmetics the only difference with the JMJ is a custom-spec pickup voiced to be similar to JMJs original '66 Mustang. So tonewise it may have a slightly more vintage vibe than the MIJ but it's still going to sound like a Mustang and unlikely to be much different to your MIJ. I haven't tried a JMJ, love the way it looks but a little pricey for me.

Me too, brings back memories of revising for school exams back in the late 60s with Then Play On blasting out in the background. Great guitarist and under rated in my opinion, RIP

The two most important things for me when looking for a band are the type of music and the people in the band. If these two feel right then the rest of it can usually be worked on if it's not already there.

Some Hartke speakers apparently have a dual voice coil design which allows impedance switching. Here's an extract from a Hartke manual: "The HyDrive HD112 has an innovative dual voice coil design that allows the cabinet to operate at either 4 or 8 ohms impedance. The cabinet has a impedance selector switch on the rear jack plate. If you are using a single speaker cabinet, and the amplifier has a minimum impedance of 4 ohms, set the HyDrive HD112 impedance selector switch to 4-ohms to get the maximum power from the amp. If you are using two HyDrive HD112 together in parallel, for a total impedance of 4 ohms, or adding a HyDrive HD112 to your current rig, set the impedance selector switch to 8 ohms."